1. Field of the Invention
The present invention relates to a twin clutch type speed change control system suitable for use in a vehicle such as a motorcycle.
2. Description of Background Art
Conventionally, a twin clutch type speed change control system is known that includes a transmission mechanism having a plurality of gear trains for odd-ordinal gear positions and even-ordinal gear positions. A pair of clutches are linked respectively to both of the odd-ordinal and even-ordinal gear position gear trains. The transmission mechanism is capable of power transmission by selectively using one of the gear trains wherein one of the clutches is engaged and the other of the clutches is disengaged during a normal operation with a fixed gear position so as to transmit power by use of one of the gear trains linked to the engaged clutch and to develop a condition where power transmission can be performed by use of a preliminarily selected one of the gear trains linked to the disengaged clutch. Starting from this condition, the engaged clutch is disengaged and the disengaged clutch is engaged, whereby changeover between the odd-ordinal gear position and the even-ordinal gear position is performed. See, for example, Japanese Patent Laid-Open No. 2007-177904.
The transmission mechanism can perform power transmission by selectively using one of the gear trains through a process in which a slide member rotated as one body with a support shaft in each of the gear trains is mutually non-rotatably engaged with a free gear mutually rotatable in relation to the support shaft.
During the above-mentioned normal operation, in the disengaged clutch, a component part on the drive source side is rotated idly relative to a component part on the gear train side. In this instance, a sound based on a mechanical play between the component part on the drive source side and the component part on the gear train side may be generated. A need exists for an improvement with respect to the sound generated.